JP3337457B2 - Screw type jack device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw jack device which can be used, for example, for adjusting the height of furniture.

[0002]

2. Description of the Related Art In a screw type jack device, two members are moved toward and away from each other by jack means comprising a combination of a screw shaft and a female screw body screwed into the screw shaft.
In this type of screw jack device, a stopper is provided to prevent the two members from moving relative to each other beyond the stroke end of the approaching / separating movement when regulating the stroke end of the jack means.

In such a conventional configuration, when the two members reach the stroke end of the approach / separation movement and the stopper comes into contact with the other side, the rotational operation resistance of the rotational operation shaft for driving the screw type jack means is reduced. The rotation operation may be terminated here, but the change in the load resistance at the stroke end between the two members, in which only one pitch of the screw is relatively moved by one rotation of the screw shaft, is accurately captured and instantaneous. It is practically impossible to complete the rotation operation, and in most cases, the rotation operation will be continued until the rotation operation of the screw jack means becomes almost impossible. As a result, the meshing portion between the screw shaft and the female screw body is strongly tightened, seizure occurs in the meshing portion, the next reverse rotation operation becomes very difficult, and furthermore, breakage of each portion and The service life was reduced.

In order to solve such a problem, as disclosed in Japanese Patent No. 2888994, a radially protruding end of a screw shaft having one end supported on one member so as to be able to rotate only is provided. A protrusion is provided on the other member side to which the female screw body is fixed, and at least one stroke end of the relative approach / separation movement of the two members abuts on the rotational side of the protrusion and the screw shaft. There has been proposed a configuration in which a stopping portion for preventing rotation of the screw is provided. However, this configuration has a jack in which a screw shaft is supported by one member in a cantilever manner such that it can only rotate, and a female screw body is fixed to the other member. The screw shaft is fixed to one member, the female screw body is supported by the other member so that it can only rotate, and the screw means is used for a jack means of a type that rotates the female screw body. Can not do it.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a screw-type jack device which can solve the above-mentioned conventional problems. In the drawing, the screw type jack means (jack units 15a to 15d) and the rotary operation shaft 27 are shown.
And a power transmission means 32 including rotating shafts 33 to 36.
A cylindrical screw shaft 43 that is relatively movable only in the axial direction and rotates integrally with the middle rotary shaft 33 is externally fitted, and an end portion of the cylindrical screw shaft 43 is provided with a protrusion 44 that protrudes in a radial direction. On the fixed frame (jack mounting frame 10a) side, a female screw hole 45 that is screwed into the cylindrical screw shaft 43 and when this screw type jack means (jack units 15a to 15d) reaches at least one stroke end. A stopper 46 is provided to stop the rotation of the rotating shaft 33 in the transmission means 32 by contacting the projection 44 at the end of the cylindrical screw shaft.

When the jack device of the present invention having the above-described structure is implemented, the cylindrical screw shaft 43 has a cylindrical screw shaft main body 47 which is loosely fitted to the rotating shaft 33 in the transmission means 32, and a cylindrical screw shaft. And a flange 48 fixed to one end of the main body 47. The flange 48 has a projection 4 at the end of the cylindrical screw shaft.
4 is projected, and a detent engaging portion 48 is engaged with a detent portion 33 a formed in the shaft hole of the flange 48 in the axial direction of the rotating shaft 33 in the transmission means 32.
a can be provided.

The female screw hole 45 on the fixed frame (jack mounting frame 10a) side is formed in a plate 49 attached to the fixed frame (jack mounting frame 10a), and the cut and raised tongue formed in the plate 49 is formed. The piece can be the stopper 46.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a furniture supporting apparatus to which a screw type jack device according to an embodiment of the present invention is applied. FIG. 2 is a furniture support device attached to the bottom of FIG. The furniture support device 1 includes an outer trolley 3, an inner trolley 4, a moving wheel 5, and a screw jack device 6.

The outer wheel base 3 is a rectangular frame formed by connecting both ends of front and rear plates 7 made of wooden or synthetic resin parallel to the longitudinal direction of the furniture body 2 with thin plates 8 such as an iron plate. And the bottom plate 2b of the furniture main body 2 (FIGS. 5 and 6) so that the outer surface of the furniture main body 2 and the outer side surfaces 2a at both ends in the longitudinal direction of the furniture main body 2 are substantially flush.
Wheel mounting frames 9a, 9b located between the front and rear side plates 7 near both ends.
The jack mounting frames 10a and 10b adjacent to the inside of the wheel mounting frames 9a and 9b and the intermediate frame 11 located between the jack mounting frames 10a and 10b are connected to the upper end of the outer base wheel 3 (furniture body 2). Bottom)
It is erected to be flush. The moving wheels 5
It is attached to the front and rear ends of the wheel attachment frames 9a and 9b. Note that the wheel support frames 9a, 9b and the jack mounting frames 10a, 10b may be integrally formed.

The inner wheel 4 is formed by the front and rear side plates 7 of the outer wheel 3.
Wooden or synthetic resin front and rear side plates 12 adjacent to the inside of
Are connected to each other by a thin plate material 13 such as an iron plate adjacent to the inside of the thin plate material 8 at both ends of the outer trolley 3. Between both side plates 12, jack mounting frames 10a, 10
b so that the jack receiving frame 14 is located just below
a, 14b are installed so as to be flush with the lower end of the inner wheel 4.

The screw type jack device 6 is a jack unit (screw type jack means) mounted on the lower side of the front and rear ends of the jack mounting frames 10a and 10b of the outer undercarriage 3.
15a to 15d, and an operation unit 16 attached to the lower front end of the intermediate frame 11.

As shown in FIGS. 4 to 6, each jack unit 15a to 15d includes a jack mounting frame 10a,
A casing 17 fixed to the casing 10b; a rotating body 18 having a female screw hole supported in the casing 17 so that only the axis of rotation can rotate in a direction in which the axis is vertically up and down;
Screw shaft 20 screwed into female screw hole portion 19 penetrating up and down of 8
The lower end of the screw shaft 20 is fixed to the jack receiving frames 14a and 14b of the inner base wheel 4. At the upper end of the rotating body 18, a downward bevel gear 21 is concentrically connected. Reference numeral 22 denotes a thrust bearing interposed between the jack mounting frames 10a, 10b of the outer trolley 3 and the rotating body 18, and 23 denotes a thrust bearing mounted on the jack mounting frames 10a, 10b of the outer gantry 3. The through hole is provided concentrically with the screw shaft 20 and allows the screw shaft 20 to protrude upward from the rotating body 18.

An example of a method of attaching the lower end of the screw shaft 20 to the jack receiving frames 14a and 14b will be described. A square seat plate portion 20a is integrally formed at the lower end of the screw shaft 20, and the square seat plate portion 20a is connected to the jack. Receiving frame 14
The jack receiving frames 14a, 14b are sandwiched between the cut-and-raised tongue pieces 24 projecting from the a, 14b and stopped.
4b and the screw shaft 20 are fastened and fixed with one fastening screw 25. In the jack receiving frames 14a and 14b, a concave portion 26 into which the head of the fastening screw 25 is fitted is formed by press working, and the screw shaft 20 is supported above the concave portion 26.

As shown in FIG. 6, the operation unit 16 has a vertical rotation operation shaft 27 supported only on the intermediate frame 11 so as to be able to rotate only, and is fixed to the lower end of the rotation operation shaft 27 and is attached to the intermediate frame 11. It comprises a bevel gear 29 provided inside a casing 28, and an operation handle 30 detachable from the rotation operation shaft 27.
The rotary operation shaft 27 includes a square shaft portion 27a protruding into a handle storage portion 31 with a detachable lid plate provided on a bottom plate 2b of the furniture main body 2 with the outer wheel 3 attached to a lower side, By externally fitting the cylindrical shaft portion 30a with a square hole of the operation handle 30 to the square shaft portion 27a, the rotation handle 27 can be operated to rotate in any forward or reverse direction by the operation handle 30. The unused operation handle 30 can be stored in the handle storage portion 31 of the bottom plate 2b.

As shown in FIG. 4, each jack unit 1
The rotating body 18 having female screw holes 5a to 15d and the rotating operation shaft 27 of the operation unit 16 are linked to each other by a transmission means 32. The transmission means 32 includes rotating shafts 33 and 34, both ends of which are supported by casings 17 of jack units 15a, 15c and 15b, 15d forming a front-rear pair, a casing 17 of a pair of front left and right jack units 15a, 15b, and an intermediate part thereof. Casing 28 of the operating unit 16
And rotating shafts 35 and 36, both ends of which are supported. A jack unit 1 is provided at both ends of the rotating shafts 33 and 34.
Bevel gear portion 21 of rotating body 18 having female screw holes 5a and 15c
Bevel gears 37a, 37b and 38a, 38b that mesh with the bevel gears 40a, 40b that mesh with the bevel gear portion 21 of the rotating body 18 with female screw holes of the jack units 15a, 15b are provided at both ends of the rotating shafts 35, 36. 41a and bevel gears 40b and 41b that mesh with the bevel gear 29 attached to the rotary operation shaft 27 of the operation unit 16 are attached.

A stopper means 42 is also provided on the rotating shaft 33 provided between the jack units 15a and 15c. This stopper means 42 is provided in FIGS.
As shown in FIG. 8, a cylindrical screw shaft 43 that can move relative to the rotation shaft 33 only in the axial direction and rotates integrally, and a protrusion 44 that protrudes radially from an end of the cylindrical screw shaft 43.
A female screw hole 45 provided on the jack mounting frame 10a side and screwing into the cylindrical screw shaft 43; and the cylindrical screw shaft end when the inner wheel 4 is lowered to the outer wheel 3 to the lower limit. The rotation shaft 3 is brought into circumferential contact with the projection 44 of the portion.
3 and a stopper 46 for stopping the rotation.

More specifically, the cylindrical screw shaft 43 is composed of a cylindrical screw shaft body 47 that is loosely fitted to the rotating shaft 33 and a flange 48 fixed to one end of the cylindrical screw shaft body 47. The flange 44 is provided with the projection 44 protruding therefrom, and the flange 48 has a notch flat rotation preventing portion 33a formed at two locations in the diameter direction formed continuously with the rotary shaft 33 in the axial direction. A detent engaging portion 48a to be engaged is provided. The female screw hole 45 is formed in a plate 49 attached to the jack mounting frame 10a, and the cut-and-raised tongue formed in the plate 49 serves as the stopper 46.

According to the furniture supporting apparatus 1 having the above-described structure, as shown in FIG. 1, the lower end of the inner wheel 4 is landed by lowering the inner wheel 4 with respect to the outer wheel 3 (see FIG. 1). The furniture main body 2 is raised with respect to the floor together with the moving wheels 5 from the floor, and the upper end of the furniture main body 2 is brought into contact with the ceiling, so that the furniture main body 2 is moved between the floor and the ceiling. Can be stretched and fixed. When the furniture body 2 is moved, the lower end of the inner wheel 4 is raised from the floor by raising the inner wheel 4 with respect to the outer wheel 3 as shown in FIG. By lowering the furniture main body 2 with respect to the floor surface together with the wheel 5), the furniture main body 2 can be supported on the floor surface by the moving wheels 5 and the upper end thereof can be separated from the ceiling surface.

As shown in FIG. 6, the operation of raising and lowering the inner wheel 4 with respect to the outer wheel 3 is performed by setting the operation handle 30 on the rotary operation shaft 27 of the operation unit 16 from the inside of the furniture main body 2. The rotation is performed by rotating the rotation shaft 27. The rotation of the rotary operation shaft 27 is performed by rotating the bevel gears 29, 40b, 41b, the rotating shafts 35, 36, the bevel gears 40a, 41a, and the bevel gear unit 21.
Through a pair of jack units 15a, 1 on the front left and right sides.
5b is transmitted to the rotating body 18 having the female screw hole, and the bevel gear 3 is transmitted from the bevel gear portion 21 of the rotating body 18 having the female screw hole.
7a, 38a, rotating shafts 33, 34, bevel gears 37b, 38
b, and via the bevel gear portion 21, the rotating body 18 with female screw holes of the pair of jack units 15 c and 15 d on the rear side
Is transmitted to

When the rotating bodies 18 with female screw holes of all the jack units 15a to 15d are simultaneously driven to rotate, each screw screwed into each female screw hole 19 and the lower end thereof is fixed to the inner base wheel 4 side. The shafts 20 are driven up and down. At this time, the jack units 15a to 15a are moved so that the screw shafts 20 move in the same direction and at the same speed at the same speed.
and the transmission means 32. By simultaneously lowering the screw shafts 20 of the jack units 15a to 15d at the same speed, the inner wheel 4 can be lowered in parallel. By simultaneously raising the screw shaft 20 at the same speed, the inner base wheel 4 can be raised in parallel.

The cylindrical screw shaft 43 of the stopper means 42 rotates integrally with the rotary shaft 33 by the engagement between the flange 48 and the rotary shaft 33 when the inner base wheel 4 is raised and lowered. The threaded engagement with the female screw hole 45 on the 49 side moves the shaft in the axial direction. In the above embodiment, the moving direction of the cylindrical screw shaft 43 when the inner wheel 4 is lowered is configured so that the flange 48 approaches the fixing plate 49, and the inner wheel 4 is moved downward. Is reached, the protrusion 44 of the flange 48 comes into contact with the stopper 46 on the fixing plate 49 side in the circumferential direction.

Therefore, when the interior pedestal 4 is lowered with respect to the outer pedestal 3 and the furniture body 2 is installed so as to be stretched between the floor surface and the ceiling surface, the height of the ceiling surface is higher than expected.
If the upper end of the furniture body 2 does not contact the ceiling surface even when the inner wheel 4 descends to the outer wheel 3 just before the lower limit, the inner wheel 4 descends to the outer wheel 3 to the lower limit. When
The protrusion 44 of the cylindrical screw shaft 43 that moves in the axial direction while rotating integrally with the rotation shaft 33 is a stopper 46 on the fixed plate material 49 side.
In the circumferential direction to prevent the rotation of the rotating shaft 33. That is, further rotation of the operation handle 30, that is, lowering operation of the inner wheel 4 is automatically prevented.

When the inner wheel 4 is raised with respect to the outer wheel 3 so that the moving wheels 5 are placed on the floor and the furniture body 2 is lowered toward the floor, the landing of the moving wheels 5 must be confirmed. The rotation operation of the operation handle 30 may be terminated, but since the operation handle 30 is continuously rotated, the inner wheel 4 continues to rise with respect to the outer wheel 3, and the upper end of the screw shaft 20 is moved to the furniture body 2.
When it is necessary to prevent the member on the outer pedestal 3 side and the member on the inner pedestal 4 side from contacting each other in the vertical direction, the cylindrical screw shaft 43 shown in FIG. Is moved in the opposite direction to the rotation of the inner base wheel 4 when the inner base wheel 4 is lowered. At this time, a stopper similar to the stopper 46 is disposed on the side where the flange 48 moves closer or A protrusion similar to the protrusion 44 is also provided on the opposite end of the screw shaft 43, and a stopper is provided corresponding to the protrusion (for example, the stopper 4 is fixed to the stopper 4).
(A stopper is provided so as to protrude to the opposite side from 6.)
Thus, in the same operation as the above operation, when the inner wheel 4 rises to the predetermined height with respect to the outer wheel 3,
Can be prevented, and further rotation of the operation handle 30 cannot be performed.

It is to be noted that the screw pitch of the cylindrical screw shaft 43 is made larger than that of a general screw shaft so that the protrusion of the cylindrical screw shaft 43 and the stopper 46 of the fixed frame can overlap at the stroke limit. It is desirable to make it as large as possible. Also, rotating shaft 3
3 is a spline shaft, or a ridge or a concave groove (key groove) is provided on the rotating shaft 33 in parallel with the axial direction, and a cylindrical screw shaft 43 (the cylindrical screw shaft main body 47 or the flange 48) is provided on the rotating shaft 33.
Can be externally fitted only in the axial direction.

[0025]

According to the screw type jack device of the present invention which can be implemented as described above and can be applied to a furniture support device, etc., the transmission means between the screw type jack means and the rotary operation shaft is provided. Utilizing a rotating shaft, a cylindrical screw shaft that moves in the axial direction while rotating in conjunction with the screw jack means is provided, and at least one stroke end of the screw jack means, the cylindrical screw shaft side And the stopper on the fixed frame side are brought into contact with each other in the rotation direction of the cylindrical screw shaft to directly prevent the rotation of the rotation shaft. Therefore, the screw type jack means rotates in the axial direction while rotating. For example, as shown in the embodiment, even if there is a screw type embodiment means of rotating a rotating body with a female screw hole which is screwed into a fixed screw shaft, the screw type embodiment means, Type jack An operator who rotates the rotary operation shaft can easily and reliably know the moment when the screw type embodiment means has reached the stroke limit, and the engaging portion between the screw shaft and the female screw body as in the related art. There is no fear of tightening.

Therefore, the meshing portion between the screw shaft and the female screw body is not seized as in the prior art, and the next reverse rotation operation is not made very difficult. Damage can be prevented and the useful life of the device can be extended.

Further, according to the structure of the present invention, the screw shaft and the rotating body with the female screw hole constituting the screw type jack means themselves are moved in the axial direction while rotating in conjunction with the screw type embodiment means. Since a cylindrical screw shaft is used, it can be set arbitrarily at either end of the stroke of the approaching / separating movement of the two members moved closer / separated by the screw-type jack means, at any end, or between both ends of the stroke. At the end of the stroke, the movement of the two members toward and away from each other can be prevented by the circumferential contact between the projection and the stopper.

According to the second aspect of the present invention, the cylindrical screw shaft which moves in the axial direction while rotating in conjunction with the rotation of the transmission rotary shaft from the rotary operation shaft to the rotary member having the female screw hole is provided. It can be easily and easily configured, and can be implemented at low cost. Further, according to the configuration of the third aspect, the female screw hole and the stopper on the fixed frame side can be easily and easily configured, so that the cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is a front view showing a furniture supporting device in a furniture installed state.

FIG. 2 is a front view showing the furniture supporting device in a state where furniture can be moved.

FIG. 3 is a bottom view of the furniture support device.

FIG. 4 is a cross-sectional bottom view of the furniture support device.

FIG. 5 is a longitudinal sectional view taken along line AA of FIG. 4;

FIG. 6 is a longitudinal sectional view taken along line BB of FIG. 4;

FIG. 7 is a longitudinal sectional side view showing details of a stopper means.

FIG. 8 is a vertical sectional front view of the stopper means.

[Description of Signs] 1 Furniture support device 2 Furniture main body 3 Outer pedestal 4 Inner pedestal 5 Moving wheel 6 Screw type jack device 10a, 10b Jack mounting frame (fixed frame) 11 Intermediate frame 15a to 15d Jack unit (screw type) Jack means) 16 operating unit 18 rotating body with female screw hole 19 female screw hole 20 screw shaft 21 bevel gear part 27 rotating operation shaft 29, 37a to 38b, 40a to 41b bevel gear 32 transmission means 33 to 36 rotating shaft 33a of rotating shaft 33 Notch flat rotation preventing part 42 Stopper means 43 Cylindrical screw shaft 44 Projection 45 Female screw hole 46 Stopper (cut-up tongue piece) 47 Cylindrical screw main body 48 Flange 48a Detent engaging part 49 Fixed plate material

Claims (3)

(57) [Claims] 1. A screw type jack device in which a screw type jack means and a rotary operation shaft are interlocked and connected by a transmission means including a rotation axis, wherein the screw type jack apparatus is relatively movable only in the axial direction with respect to the rotation shaft in the transmission means. A cylindrical screw shaft that rotates integrally with the outer periphery of the cylindrical screw shaft is provided at the end of the cylindrical screw shaft. A female screw that is screwed to the cylindrical screw shaft is provided on the fixed frame side. A hole and a stopper for stopping the rotation of the rotating shaft in the transmission means by abutting on the projection at the end of the cylindrical screw shaft when the screw type jack means reaches at least one stroke end. , Screw type jack device. 2. The cylindrical screw shaft comprises: a cylindrical screw shaft body loosely fitted to a rotating shaft in the transmission means; and a flange fixed to one end of the cylindrical screw shaft body. A protrusion at the end of the cylindrical screw shaft is projected, and a detent for engaging with a detent part formed in the axial hole of the flange and axially continuous with the rotating shaft in the transmission means. The screw jack device according to claim 1, wherein an engagement portion is provided. 3. The fixing device according to claim 1, wherein the female screw hole on the fixed frame side is formed in a plate material attached to the fixed frame, and a cut-and-raised tongue piece formed in the plate material functions as the stopper. The screw-type jack device as described.